Numerical arithmetic should look to children like a simpler and faster way of doing things that they know how to do already, not a set of mysterious recipes for getting right answers to meaningless questions.
John Holt, How Children Fail, p. 101
See also Paul Lockhart.
(Last month's started a little late, I thought I'd bring it back to its original schedule.)
A monthly thread for posting any interesting rationality-related quotes you've seen recently on the Internet, or had stored in your quotesfile for ages.